JAX-RS 2 print JSON request

2022-09-02 19:36:50

我希望能够从请求中打印 JAX-RS 2 JSON 有效负载,而不管在我的应用程序服务器上的实际实现如何。

我已经在SO上尝试了建议的解决方案,但都包含来自实际实现的二进制文件(如泽西岛和类似),并且我只允许在我的应用程序中使用javaee-api v 7.0。

我尝试过在我的客户端上实现 ClientRequestFilter 和 ClientResponseFilter,但它们不包含序列化实体。

下面是一个客户端示例:

WebTarget target = ClientBuilder.newClient().register(MyLoggingFilter.class).target("http://localhost:8080/loggingtest/resources/accounts");
Account acc = target.request().accept(MediaType.APPLICATION_JSON).get(account.Account.class);

以下是MyLoggingFilter的实现:

@Provider
public class MyLoggingFilter implements ClientRequestFilter, ClientResponseFilter {

    private static final Logger LOGGER = Logger.getLogger(MyLoggingFilter.class.getName());

    @Override
    public void filter(ClientRequestContext requestContext) throws IOException {

        LOGGER.log(Level.SEVERE, "Request method: {0}", requestContext.getMethod());

    }

    @Override
    public void filter(ClientRequestContext requestContext, ClientResponseContext responseContext) throws IOException {
        LOGGER.log(Level.SEVERE, "Response status: {0}", responseContext.getStatus());
    }        
}

答案 1

因此,在尝试实现此内容时,需要考虑几件事

  1. 对于请求实体,您将希望序列化由框架处理,这意味着您不希望执行类似操作

    @Override
    public void filter(ClientRequestContext requestContext) {
        Object entity = requestContext.getEntity();
        String serialized = serializeEntity(entity);
        log(serialized);
    

    在这里,您自己序列化它,也许使用Jackson或其他东西。你可以这样做,但它可以处理的类型有点有限。如果让对象以框架已经处理的方式进行序列化,则框架将能够支持比 JSON 更多的类型。ObjectMapper

    为了让框架处理序列化,并且仍然能够获取序列化的数据,我们需要使用WriterInterceptor。我们可以做的是将实体输出流设置为 a ,然后让框架将请求对象序列化到我们的 ,然后 afterwords 记录这些字节。这就是泽西岛如何处理这个问题。ByteArrayOutputStreamByteArrayOutputStreamLoggingFilter

  2. 对于响应,在我们的筛选器中,我们需要从响应流中提取数据,但我们还需要确保流仍然具有数据,因为它尚未针对客户端进行反序列化。若要执行此操作和流,请假定支持标记。如果没有,请将其包装在 .同样,这就是泽西岛如何处理这个问题。mark()reset()BufferedOutputStreamLoggingFilter

下面是一个完整的简单实现。其中大部分是直接从泽西岛中获取的,尽管它只是为了您的用例而被剥离。泽西岛记录了许多其他信息,而不仅仅是实体。我遗漏的一件事是检查字符集。我刚刚使用了硬编码的UTF-8,因为泽西岛使用的类是泽西岛特定的。如果要使筛选器对其他字符集更具通用性,则可能需要考虑修复此问题。LoggingFilterLoggingFilterMessageUtil

import java.io.BufferedInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.logging.Logger;
import javax.annotation.Priority;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.client.ClientRequestContext;
import javax.ws.rs.client.ClientRequestFilter;
import javax.ws.rs.client.ClientResponseContext;
import javax.ws.rs.client.ClientResponseFilter;
import javax.ws.rs.ext.WriterInterceptor;
import javax.ws.rs.ext.WriterInterceptorContext;

@Priority(Integer.MIN_VALUE)
public class EntityLoggingFilter implements ClientRequestFilter, ClientResponseFilter, WriterInterceptor {

    private static final Logger logger = Logger.getLogger(EntityLoggingFilter.class.getName());
    private static final String ENTITY_STREAM_PROPERTY = "EntityLoggingFilter.entityStream";
    private static final Charset DEFAULT_CHARSET = StandardCharsets.UTF_8;
    private final int maxEntitySize = 1024 * 8;

    private void log(StringBuilder sb) {
        logger.info(sb.toString());
    }

    private InputStream logInboundEntity(final StringBuilder b, InputStream stream, final Charset charset) throws IOException {
        if (!stream.markSupported()) {
            stream = new BufferedInputStream(stream);
        }
        stream.mark(maxEntitySize + 1);
        final byte[] entity = new byte[maxEntitySize + 1];
        final int entitySize = stream.read(entity);
        b.append(new String(entity, 0, Math.min(entitySize, maxEntitySize), charset));
        if (entitySize > maxEntitySize) {
            b.append("...more...");
        }
        b.append('\n');
        stream.reset();
        return stream;
    }

    @Override
    public void filter(ClientRequestContext requestContext) throws IOException {
        if (requestContext.hasEntity()) {
            final OutputStream stream = new LoggingStream(requestContext.getEntityStream());
            requestContext.setEntityStream(stream);
            requestContext.setProperty(ENTITY_STREAM_PROPERTY, stream);
        }
    }

    @Override
    public void filter(ClientRequestContext requestContext,
            ClientResponseContext responseContext) throws IOException {
        final StringBuilder sb = new StringBuilder();
        if (responseContext.hasEntity()) {
            responseContext.setEntityStream(logInboundEntity(sb, responseContext.getEntityStream(),
                    DEFAULT_CHARSET));
            log(sb);
        }

    }

    @Override
    public void aroundWriteTo(WriterInterceptorContext context)
            throws IOException, WebApplicationException {
        final LoggingStream stream = (LoggingStream) context.getProperty(ENTITY_STREAM_PROPERTY);
        context.proceed();
        if (stream != null) {
            log(stream.getStringBuilder(DEFAULT_CHARSET));
        }
    }

    private class LoggingStream extends FilterOutputStream {

        private final StringBuilder sb = new StringBuilder();
        private final ByteArrayOutputStream baos = new ByteArrayOutputStream();

        LoggingStream(OutputStream out) {
            super(out);
        }

        StringBuilder getStringBuilder(Charset charset) {
            // write entity to the builder
            final byte[] entity = baos.toByteArray();

            sb.append(new String(entity, 0, entity.length, charset));
            if (entity.length > maxEntitySize) {
                sb.append("...more...");
            }
            sb.append('\n');

            return sb;
        }

        @Override
        public void write(final int i) throws IOException {
            if (baos.size() <= maxEntitySize) {
                baos.write(i);
            }
            out.write(i);
        }
    }
}

另请参阅:


答案 2